autotools/configure&make support for build.rs

A build dependency to compile a native library that uses autotools or
a compatible configure script + make.

It is based on cmake-rs and
the API tries to be as similar as possible to it.

# Cargo.toml[build-dependencies]autotools ="0.2"

// build.rsuse autotools;// Build the project in the path `foo` and installs it in `$OUT_DIR`let dst =autotools::build("foo");// Simply link the library without using pkg-configprintln!("cargo:rustc-link-search=native={}", dst.display());println!("cargo:rustc-link-lib=static=foo");